using System;

public class Program

{

    private static Logger _logger;

    public static void Main()

    {

        _logger = new Logger();

        try{

            AddMedicalBillPayee();

        }

        catch(Exception ex){

            _logger.Log(ex);

        }

    }

    static void AddMedicalBillPayee() {

        try{

            throw new InvalidOperationException("You cant do that.");

        }

        catch(Exception ex){

            _logger.Log(ex);

            throw ex;

        }

    }

​

}

class Logger

{

    public void Log(Exception ex) {

        Console.WriteLine(ex);

    }

}